Volumetric type monitoring systems are known in the sector in question which allow predetermined zones to be monitored.
These monitoring systems are generally equipped with volumetric sensors which allow the accesses to the building (for example, the doors, windows etc.) to be monitored.
A first drawback of this type of security/monitoring system is due to the fact that these systems do not distinguish whether the person accessing the monitored space is authorised or not to access the space.
This means that these volumetric detection systems can only be activated in the absence of persons in the protected area and they must therefore be deactivated if that is not the case.
A drawback of these systems is that they must be kept deactivated when persons are present inside the zone being monitored: in that case, any access of unauthorised persons (malicious or otherwise) cannot be detected.
There has therefore been a long felt need for the provision of a volumetric type security/monitoring system which can be kept operational also in the presence of persons in the predetermined zone, thus guaranteeing a greater security for the occupants of the zone.